[#MDEV-17413] Crash on shutdown in my_malloc_size_cb_func, after "Forcing close of thread"..

2018-10-09 10:07:02 3224 [Note] Event Scheduler: Purging the queue. 0 events

2018-10-09 10:07:02 6120 [Note] InnoDB: FTS optimize thread exiting.

2018-10-09 10:07:33 3224 [Warning] C:\Program Files\MariaDB 10.2\bin\mysqld.exe: Forcing close of thread 10  user: 'root'

2018-10-09 10:07:33 3224 [Warning] C:\Program Files\MariaDB 10.2\bin\mysqld.exe: Forcing close of thread 9  user: 'bCEDAR57Z1C85I2'

181009 10:07:33 [ERROR] mysqld got exception 0xc0000005 ;

<...>

Server version: 10.2.14-MariaDB

key_buffer_size=134217728

read_buffer_size=131072

max_used_connections=2

max_threads=65537

thread_count=2

It is possible that mysqld could use up to

key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 136058 K  bytes of memory

Hope that's ok; if not, decrease some variables in the equation.

Thread pointer: 0x0

Attempting backtrace. You can use the following information to find out

where mysqld died. If you see no messages after this, something went

terribly wrong...mysqld.exe!my_malloc_size_cb_func()[mysqld.cc:4033]

mysqld.exe!my_malloc()[my_malloc.c:126]

mysqld.exe!net_real_write()[net_serv.cc:636]

mysqld.exe!net_flush()[net_serv.cc:382]

mysqld.exe!net_write_command()[net_serv.cc:518]

mysqld.exe!net_send_error_packet()[protocol.cc:467]

mysqld.exe!net_send_error()[protocol.cc:175]

mysqld.exe!close_connection()[mysqld.cc:2824]

mysqld.exe!close_connections()[mysqld.cc:1820]

mysqld.exe!kill_server()[mysqld.cc:2016]

mysqld.exe!handle_shutdown()[mysqld.cc:3673]

mysqld.exe!pthread_start()[my_winthread.c:62]

mysqld.exe!thread_start<unsigned int (__cdecl*)(void * __ptr64)>()[thread.cpp:115]

KERNEL32.dll!BaseThreadInitThunk()

Can be reproduced with non-responsive threads (i.e adding large sleep() before connection close), and compression being used on connection.
net_read_write would try to allocate thread-specific memory, for compression and then crash in my_malloc_size_cb_func(), since current_thd is NULL.

Normally, connections are closed from inside the connection itself, i.e current_thd != NULL, but in the specific case of closing connections from outside
it is not the case.
This can be reproduced also in 10.0, but just with DBUG version , but in 10.1+ also in release version

Commit b4ff64568c88 is the culprit, since it stopped checking for current_thd == NULL if thread-specfic memory is allocated.

[MDEV-17413] Crash on shutdown in my_malloc_size_cb_func, after "Forcing close of thread".. Created: 2018-10-09 Updated: 2018-10-09 Resolved: 2018-10-09
Status:	Closed
Project:	MariaDB Server
Component/s:	Server
Affects Version/s:	10.2.14
Fix Version/s:	10.3.11, 10.1.37, 10.2.19

[MDEV-17413] Crash on shutdown in my_malloc_size_cb_func, after "Forcing close of thread".. Created: 2018-10-09 Updated: 2018-10-09 Resolved: 2018-10-09